Method for making temporary doors



May 1, 1962 B. H. FORD 3,032,453

METHOD FOR MAKING TEMPORARY DOORS Filed April 25, 1958 v 2 Sheets-Sheet 1 ATTORNEYS.

May 1, 1962 B. H. FORD METHOD FOR MAKING TEMPORARY DOORS 2 Sheets-Sheet 2 Filed April 25, 1958 ATTORNEYS.

METHOD FOR MAKENG TEMPGRARY DOORS Barton H. Ford, Omaha, Nebn, assignor, by mesne as signments, of one-half to international Paper Company, New York, N.Y., a corporation of New York,

and one-half to The Stanley Works, New Britain, Conn.,

a corporation of Connecticut Filed Apr. 25, 1958, Ser. No. 730,901 3 Claims. (Cl. 156-207) This invention relates to a method of making temporary doors and apparatus therefor, and, more particularly, to doors for a grain-carrying freight car which prevent the escape of grain, or like material, from the car.

This application is a continuation-in-part of my cperslging application, Serial No. 667,187, filed June 21,

In the transportation of grain in a boxcar, or the like, it is necessary to provide special closures that extend across the bottom portions of the doorways on each side of the freight car. The cars permanent doorway closures, the storm doors, are incapable of sealing the doorway to prevent escape of the granular material. The sealing type closures should be temporary, since a freight car may not always be used for hauling grain. Conventionally, these temporary closures have been constructed of relatively flexible materials like paper board, and have been nailed or otherwise secured along their sides to the inside of the car door framework.

From this, it can be seen that after not too many temporary doors have been applied to the framework, the framework becomes weakened. This might be costly in that an entire shipment could be lost or ruined. Therefore, it would be desirable for a closure or panel of a temporary nature to be provided which could'be secured to unweakened portions of doorway framing, and thereby avoid the possibility of the temporary closure being detached from the framework.

As pointed out above, temporary closure panels are usually constructed of inexpensive materials. Of these, paper board is generally preferred for this purpose. Currently, two types of paper board closures are usually employed, one'with corrugations and one without a corrugated layer. The noncorrugated form is considered lacking in suitable strength. Where corrugations are provided in a paper board panel, the desired strength is provided. This strength is especially noticeable in the direction in which the flutes are oriented. The flutes in such a panel are ordinarily oriented vertically when the temporary closure'is installed. Additions to the strength of the panel in a horizontal direction are provided by spaced-apart fiat, relatively rigid, reinforcing bands, such as metal bands.

When spaced metal straps are employed for strengthening a panel, the technique usually employed to install the panel is to secure the straps to the framework by separating them from the sides of the panel. This is done by providing side flaps through vertically scoring the panels along lines spaced inwardly of the sides. In such case, the straps are first nailed to the door framework and thereafter nailing strips or side battens are employed to secure the flap portions to the framework.

The foregoing procedure of doubly securing a panel results in certain disadvantages. A principal disadvantage relates to the additional labor required in securing the side battens. The need for duplicate nailing produces framework weakening at an accelerated rate.

Therefore, it would be desirable to eliminate the duplicate nailing currently considered necessary. Further, it would be advantageous forthe worker installing such panels to see where the nail is to be driven into the framework, since this would minimize the chances of an in- 3,@32,453 Patented May 1, 1962 secure nailing. It is to be appreciated that this last-mentioned feature applies irrespective of Whether or not a corrugated type panel is used. Where a corrugated type panel is applied to weakened framework, resulting in an insecure union, another type of disadvantage may result. Since there is a tendency of corrugated paper board to warp in the direction in which the flutes are oriented, the stresses applied on the-nails, particularly at the bottom, might well result in complete breaking of the seal between the panel and the door frame, thus permitting grain escape.

It is an object of this invention to provide a method and apparatus for making a new type of temporary closure for a freight car, or like vehicle. Another object of this invention is to provide a method and apparatus for producing a closure which avoids the problems and disadvantages characteristic of previously-employed closures. Still another object is to provide a method and apparatus for making a new type of closure constructed of a corrugated paper board. Yet another object is to provide a method and apparatus for producing a new type of closure which permits those installing the closure to readily determine whether the closure can be secured to an unweakened portion of the doorway framework.

A further object is to provide a method and apparatus for producing temporary closures for freight cars, and the like, in which an assembled laminated panel is perforated within the Width of the flat'relatively rigid straps included within the panel. A still further object is to provide a method and apparatus in which the panels are continuously produced in the form of a web and in which the web is simultaneously perforated at a number of transversely spaced positions. A yet further object is to provide a method and apparatus for producing temporary door closures in which a plurality of continuous webs are assembled to form a reinforced laminated web and thereafter selectively perforated and severed to provide the desired panels.

Other objects and advantages of this invention will be seen as this specification proceeds.

This invention will be described in conjunction with the accompanying drawing, in which FIG. 1 is a fragmentary perspective view of the inside of a freight car showing a closure embodying teachings of this invention installed in place; FIG. 2 is an enlarged cross-sectional view taken along the line 2-2 of FIG. 1; FIG. 3 is an elevational view of an apparatus for producing panels embodying teachings of this invention; FIG. 4 is a fragmentary plan view of a panel-providing web in the process of manufacture; FIG. 5 is an enlarged fragmentary elevational view, partially in section, showing the portion of the apparatus employed to perforate the panel; and FIG. 6 is an enlarged fragmentary elevational view, partially in section, of another portion of the apparatus employed to sever the panels from a continuous web from which they are produced.

In the illustration given, the numeral 10 designates gen erally a freight car of which only one side wall 11 and the floor 12 are shown. It is believed unnecessary to reproduce the remainder of freight car 10, since such is considered unnecessary for understanding the invention here presented. Wall 11 is provided with a doorway 13, about which is disposed doorway framework 14.

Secured to framework 14 is a panel generally designated 15, which serves as a temporary closure. Panel 15, as can be seen in FIG. 2, is provided with a corrugated layer 16 centrally thereof, and outer liners 17 and 18. Interposed between outer liner 17 and corrugated layer 16 is a metal strap 19. As can be seen in FIG. 1, a numberof straps 19 are provided which are coextensive with the width of panel 15. conventionally, panel 15 is provided of a height less than the height of doorway 13 in order to permit introduction of grain through doorway 13 when panel 15 is installed in place. The space above panel 15 also permits the workman installing panel 15 to leave the inside of the car.

Panel 15 is provided with a plurality of openings 25 extending through the entire thickness thereof, as can be best seen in FIG. 2, In the illustration given, these openings are provided in the portion adjacent the end of strap 19 which is in overlapping relation with framework 14 when panel 15 is secured thereto. Nails 21 are employed to secure panel 15 to framework 14.

As can be appreciated from a consideration of FIG. 2, the flutes of corrugated layer 16 are disposed vertically when panel 15 is installed in place. The additional strength provided thereby permits panel 15 to be installed without the need of a bottom flap. Where the bottom flap is desired, panel 15 can be horizontally scored along one of the longer sides thereof to provide a flap, such as is indicated in dotted lines and designated 22 in FIG. 1.

Panels of the type shown in FIG. 1 can be conveniently produced by the apparatus shown schematically. in FIG. 3. Referring now to FIG. 3, the numeral 23 designates a roll of paper, for example, kraft paper weighing 47 pounds per 1,000 square feet. The numeral 24 designates another roll of paper which will ultimately provide the corrugated layer 16 of panel 15. Such paper may conveniently be 33 pound kraft. Paper web 25 from roll 24 is drawn through corrugating rolls 26, thence over idler roll-s 27 into press rolls 28, where it is adhesively united with web 29 from roll 23. Web 29 ultimately provides liner 18 of panel 15. Also drawn into press rolls 28 is web 30 from roll 31similar to roll 23. Web 30 ultimately provides liner 17, and is conveniently of the same character as Web 29 and, therefore, liner 18. Also drawn into press roll 28 are a plurality of spaced metal strands 32. Strands 32, which ultimately provide straps 19, can be conveniently constructed of 0.020" black steel having a width of Prior to the drawing of web 30 into rolls 28, adhesive is applied, permitting bonding of web 39 to the strands 32 and the unbonded side of web 25. Adhesive may be applied by glue rollers 29a and 30a in contact with webs 29 and 30, respectively, as seen in FIG. 3.

The united webs issuing from rolls 28 are heated and pressed together in a continuous oven enclosure 33 which is internally equipped with a plurality of opposed press rolls 34. Preferably the rolls 34 are driven at an angular speed corresponding to the rate of speed of the laminated web 35 derived from assembly paper webs 25, 29' and 30 and metal straps 32.

Thereafter, the web 35 passes through a perforationproviding station generally designated 36, which'includes a pair of circular members 37 and 38 rotatably mounted on a frame 39. Circular element 37 is equipped with a plurality of radially outwardly-extending protuberances 40 which can be seen in greater detail in FIG. 5. The perforating circularelement 37 cooperates with circular element 38 which serves as an anvil or abutment and is equipped with a plurality of protuberance-receiving indentations 41, which also can be seen in greater detail in FIG.-5. The protuberances 40 andrecesses 41 are proportioned to provide a punching action on the web 35 over and through the portions thereof in which the transversely spaced-apart straps 32 are positioned.

,'Iheprotuberances 4iland recesses 41 are confinedto onlyaminor portion of the periphery of circularelements 37 and 38 so as to provide longitudinally spaced-apart groups of perforations, as can 'be appreciated from a consideration of FIG. 4, wherein the spaced-apart groups are designated by the numerals 42 and 43. The groups of perforations 42 and43 are spaced apart ordinarily in the longitudinal dimension of the web by about the length of the panel 15. For example, corresponding perforations in each group can be spaced apart from 90 inches to 114 inches, which corresponds to the overall widths of standard freight car doorways. The perforations 44 can conveniently have a diameter of inch when the width of straps 32 is A of an inch and the longitudinally-aligned perforations can be provided on inch centers, with 6 to 10 perforations per group.

Circular elements 37 and 38, in addition to being provided with protuberances 4i and recesses 41, respectively, that are aligned so as to produce successive perforations in a given strap, are also equipped with protuberances and recesses that are transversely aligned with respect to web 35. This produces the situation seen in FIG. 4, wherein each group of perforations 42 and 43 includes perforations 44 in adjacent straps 32, with the perforations also being transversely aligned with respect to web 35. Thus, when circular elements 37 and38 cooperate to provide a punching action, a plurality of transverselyaligned perforations v44 are provided in web 35.

Frame 39 can also conveniently carry the severing mechanism generally designated 45 and shown in greater detail in FIG. 6. Thesevering mechanism 45 includes a pair of rotatably mounted knives 4'6 and 47 that rotate at the same speed as circular elements 37 and 38. As with elements 37 and.38,.the rotatablyemounted knives 46 and 47 are positioned on opposite sides of web 35 as it travels past frame 39. The angular orientation of knives 46 and 4'7 is such as to produce a severing in Web 35 intermediate the length of. a group ofperforations 42 or 43, as is indicatedby the numeral 48 in FEGS. 4 and 6. Preferably, the line of severance or cutting 48 is located centrally of the group of perforations 42, and, in the illustration given, provides three perforations oneach side of the cut. I have found that three to five openings at the end of each strap provide optimum results since then several nails can be employed, if desired, generally without the possibility of engaging an already weakened portion of the structural framework 14 of the car door.

I have'foundthatlimiting the perforations in the side portions of the panel as described above permits substantial lessening in the weight of the structurethrough the use oflightcr straps. Thisalso contributes to the over-all strength of the installed structure, since appreciably less weight of panel need be carried by the panel itself and also the framework of the grain car door.

If itis desired to provide side flaps for the panel .15, liner 18 can be scored in the direction of the flutes and along a line spaced inwardly of the vertical sides of panel 15. In such a case, it may be desirable to install addition all blades between the perforating mechanism 36 and the severing mechanism 45 to provide th desired scoring.

While, in the foregoing specification, I have set forth specific details of the invention for the purpose of illustration thereof, it will be understood that such details may be varied widely by those skilled in the art without departing from the spirit and scope of my invention.

I claim:

1. A method of producing door panels for freight cars, comprising bonding a first liner to one side of a corrugated sheet, positioning a plurality of flat metal straps in parallel relation adjacent the other side of said corrugated sheet, the length of saidstraps extending transversely of the flutes of said corrugated core bonding a second liner to the other side of ,saidcorrugated sheet, wherebysaid straps are contained between saidsecond linerand said corrugated sheet, punching the. assembled panel at spaced distances throughsaid-straps to provide openings therethrough wherebysaid panel may be secured ,to the interior of afreight car ,by inserting nails through said openings.

2. Amethod of producing panels forfreight cars comprising providing three continuous webs of paperboard, corrugating one of;said webs to provide flutes extending transversely of the length of the Web being corrugated, adhesively bonding one of the other of said webs to-said corrugated web, positioning a plurality ofmetal straps on said corrugated web adjacent the unbonded surface thereof and parallel to the length of said corrugated web adhesive- 1y bonding the third web, to the unbonded side of said corrugated web, punching said straps and united webs at spaced intervals, and transversely severing said united webs and metal straps whereby the panel produced by the severing step may be secured to the interior of a freight car by inserting nails through the punched portions.

3. A method of producing panels for freight cars, comprising the steps of advancing a pair of webs to provide outer liners, simultaneously advancing a third Web between said pair of webs to provide a corrugated core, corrugating said third web with the flutes thereof extending trans-t versely to the direction of advance, advancing in said direction a plurality of spaced-apart, flat metal straps between said third web and one of said pair of webs, applying adhesive to the faces of said pair of webs confronting said 15 2,829,701

6 third web, pressing all of said webs and straps together to provide a web panel, punching said web panel at spaced distances through said straps to provide openings through said panel, and transversely severing said web panel to provide a plurality of individual panels each with openings extending therethrough in the ends of each strap.

References Cited in the file of this patent UNITED STATES PATENTS 2,504,473 Van Antwerpen Apr. 18, 1950 2,595,087 Leslie Apr. 29, 1952 2,739,635 Seaborne et al. Mar. 27, 1956 2,794,761 Williamson June 7, 1957 Keely Apr. 8, 1958 

1. A METHOD OF PRODUCING DOOR PANELS FOR FREIGHT CARS, COMPRISING BONDING A FIRST LINER TO ONE SIDE OF A CORRUGATED SHEET, POSITIONING A PLURALITY OF FLAT METAL STRAPS IN PARALLEL RELATION ADJACENT THE OTHER SIDE OF SAID CORRUGATED SHEET, THE LENGTH OF SAID STRAPS EXTENDING TRANSVERSELY OF THE FLUTES OF SAID CORRUGATED CORE BONDING A SECOND LINER TO THE OTHER SIDE OF SAID CORRUGATED SHEET, WHEREBY SAID STRAPS ARE CONTAINED BETWEEN SAID SECOND LINER AND SAID CORRUGATED SHET, PUNCHING THE ASSEMBLED PANEL AT SPACED DISTANCES THROUGH SAID STRAPS TO PROVIDE OPENINGS THERETHROUGH WHEREBY SAID PANEL MAY BE SECURED TO THE INTERIOR OF A FREIGHT CAR BY INSERTING NAILS THROUGH SAID OPENINGS. 